Answer:
1.414
Explanation:
Snell's law states:
n₁ sin θ₁ = n₂ sin θ₂
where n is the index of refraction and θ is the angle of incidence (relative to the normal).
The index of refraction of air is approximately 1. So:
1 sin 45° = n sin 30°
n = sin 45° / sin 30°
n = 1.414
Round as needed.
Answers:(a) 
μT
(b) 
μm
(c) f =
Explanation:Given electric field(in y direction) equation:

(a) The amplitude of electric field is

. Hence
The amplitude of magnetic field oscillations is

Where c = speed of light
Therefore,

μT (Where T is in seconds--signifies the oscillations)
(b) To find the wavelength use:



μm
(c) Since c = fλ
=> f = c/λ
Now plug-in the values
f = (3*10^8)/(0.4488*10^-6)
f =
Average velocity = (800+1600)/(4+10)
= 171.42m/s
The steps in the heating of a metal seat in a park are:
Step 1: Heat travels from the sun to Earth
Step 2: Heat travels through atmosphere to the top of the seat
Step 3: Heat from the top of the seat travels through the seat to the lower parts of the seat.
-- Heat is transferred by radiation in Step 1 and Step 2. <em>(B)</em>
-- From the top of the seat to the bottom, heat is transferred by conduction.
There's no convection happening anywhere in the park-hot-seat scenario.
Explanation:
Total mass=100+10=110
Total weight=mass×gravitational field strength
=110×10
=1100N
Work done=force×distance
=1100×10
=11000J
<em>Please mark me as brainliest if this helped you!</em>